Method and apparatus for coating materials and articles



Jan. 27, 1942. I H. w. PLEISTER 2,271,094

METHOD AND APPARATUS FOR COATING MATERIALS AND ARTICLES Filed June 22, 194O 3 Sheets-Sheet l Jan. 27, 1942. H, w, PLE|$TER 2,271', 094

METHOD AND APPARATUS FOR COATING MATERIALS AND ARTICLES Filed June 22, 1940 3 SheetsSheet 2 Jan. 27, 1942. H. w. PLEISTER 2,271,094

METHOD AND APPARATUS FOR COATING MATERIALS AND ARTICLES Filed June 22, 1940 3 Sheets-Sheet3 ?atente Jan. 1942 METRO APPARATUS son comma msrnnmns AND narrows new w. Zleister, Westfield, N. a, ham. to f f Diamond Expansion Bolt alompan'y linc Gal-- wood, N. ii a corporation or New Jersey Application nine 22, 1940, Serial No. a so scams. (clans) I N H These percussion blows may be given in. various invention covers a method and apparatus ior coating separate and independent metal ob= .iects or regular, or more or less irregular-contour, with a coating of metal, usually zinc,alu-

minum, tin, alloy, or any metal that will melt at a lower temperature than the articles to be coated. It is particularly adapted to coat relatively small metal articles, as for example nails,

screws, nuts, bolts, washers, tacks, and other small metal ObjGCtSfiES for example spikes, wire staples, or any such objects. My invention also covers the coated articles processed by my invention. i

I use my invention primarily in galvanizing by the hot process in which zinc or spelter is used. In my process the separate articles of regular or irregular contour, to be coated, are immersed in a bath of molten zinc or spelter, or in a bath of any other molten metal if that metal is desired to coat the articles.

The metal objects are-then removed from the molten bath and immediately subjected, in a.

basket or other container, to centrifugal action to remove the surplus'coating material, the centrifugal action automatically throwing the sep rate articles over the'rim. of the whirling basket or other container, allowing them to drop intoa cooling bath of water or other fluid.

Further by my process the travel of the separate independent articles out of the basket is temporarily impeded to insure that all the different coated articles shall have all the surplus coating metal removed before they are automatically thrown over the lip of the basket or other container. To further this actionand toinsure the'complete and uniform covering of the arti else so there will be no blisters, rough spots,

ways to thefarticles while-yin thevcentrifugal basket. Ihaveobtained.perfectresultsbyletting the centrifugal action thmwthetreatedf articles, against non-'rotating'baille {plates mounted in thei rotating basket or container. Their. action'will' be more fully hereinafter described.

My method of removing all thesurplus coating material from the articleswhilethey are substantially at their maximum temperature and f under the actionof centrifugal forceis continu ous. The coated articles convenient, there being no stopping or starting of the machine for the treatment oieach basketi 'ful of articles processed, thereby. insuring a great.-

saving of timewith less wear on the machineand motor, and less labor required per ton ofarticles 1 treated.

My invention further relates to certain meanods, combinations, sub-combinations, and articles of manufacture as will be more fully hereinafter described and pointed out in the claims.

In the accompanying drawings I have shown one illustrative form of apparatus, simply by 1 way of example, but my improved method is not to be limited to this apparatus.

Fig. 1 is a plan view of one .form of apparatus for carrying out my improved method.

blow-holes, or excess material at any point on the articles; that the coating material will be smooth and ductile, and that there will be no adhesion between any two or more articles, I subject the coated articles while in the basket and while under centrifugal action, and while substantially at which not onlyseparate any two or more coated articles, which might have adhered to each other, but the percussion blows assist in removing'any surplus coating metal from the articles.

These successive percussion blows on the articles while in the whirling, basket also insure a smooth, even, and ductile coating. These blowstheir maximum temperature, to percussion blows,

Fig.4 is across-section online 4-4 of Fig. .2; Fig. 5 is a vertical section on line 5, 5 of Fig. 3; Fig. 6 is a cross-section online 6, 6 of Fig. 2;

i Fig. 'Hsa cross-section on line 1, .1 of Fig. 2;

' Fig. 8 is a side elevation of a wire nail, being one of the great number of separate articles which are coated by my method;

Fig. 9 is a side elevation of the same nail bent se'vendegrees;

Fig. 10 is a sideelevation of the same nail ben twelve degrees;

Fig. 11 is a side elevation of the same nail bent one hundred and eighty degrees. I

In the machina'illustrated by way of example, the triangular frame I consists of three horizontal plates 2, 2 secured to the vertical legs 3, 3, preferably formed of channel irons, secured .to the brackets I, 4 in any suitable manner such as by the rivets 5. v Y

On the frame I is mounted a motor 6, provided with a flexible coupling 1 to drive the shaft t mounted in the horizontal bearing...8. On the V maybe fediintomyma 1 chine in. any suitable-manner as may be found other end of this shaft 8 is mounted a bevel gear ll, secured to theshaft in any suitable manner as by the pin l.

This horizontal bearing 9 is formed in the i bracket 12, secured to the plate II by any suitment 20, supported on the bracket II by a roller bearing i9. On the shaft I1 is mounted a sleeve 2| carrying a bevel gear 22 in mesh with the bevel gear III. The sleeve 2| is secured to the shaft H in any suitable manner as by a pin 23.

On the lower end of the drive shaft I1 is car- ;ried the perforated basket I8, preferably by reducing the diameter of the shaft slightly to iorma shoulder 24, so that a cone shaped collar II mounted upon the reduced portion of the shaft |1, will permit the nut 26 to clamp and hold the bottom of the basket as the nut is screwed up on the thread 21 on the end of the shaft H. The washer 25' may be located between the nut It and the bottom of the bracket l8, Fig. 2. This cone-shaped collar 25 also spreads the articles to be coated towards the sides of the basket ll, and prevents a'dead" spotin the basket, where the full force of the centrifugal action would not be exerted upon the articles when fed into the basket through the funnel 28.

This funnel 28 has a lip 29 and a cylindrical portion 30, which extends well down into the basket I8, see Fig. 2. The funnel 20 is immovably secured to the cover 3| by the bracket 32 and the bracket 33, the ends of this latter bracket being secured by the bolts 34, 34 to the channel iron 2, see Figs. 2 and 1.

On the cylindrical portion 30 of the funnel 28, I mount my baflle or spider unit 88, Figs. 5, 2 and 3, which is preferably adjustable vertically, but when once adiustedis immovable.

This baffle unit or spider 36 consists of a cylindrical sleeve 31 (Figs. 3 and ,-provided with two arms 38, 18, each arm being provided with an elongated adjusting slot 39. Mounted fast on the cylindrical sleeve 31 are one or more baiile plates 40, 40, two being shown Ly way of example. These baffle plates 40, 40 are provided with openings 4|, 4|, preferably in the form of cut-away portions in the baffle plates, though of course they could be formed in any other suitable manner. Openings 43, 43, Fig. 3, between the bafile plates 40, 4B and the sleeve 31 are also preferably provided.

I preferably arrange the outer rim of each baiile plate 40 at a lower elevation than the center of the baffle plate so asto form an inclined surface 44, Fig. 5.

The openings 4|, 4| and 43, 43, in each baffle plate 40 are preferably arranged staggered with relation to the similar openings in the next higher battle plate, to prevent too rapid exit of the coated articles from the basket l8, andto insure that each coated article, at one or more points in its travel out of the perforated basket, will receive a tap or percussion blow by being thrown against one or more of the fixed bafile plates 40.

After adjusting the bailie or spider unit 36 at the desired position on the cylindrical portion of the fixed funnel 30, it is held in that adjusted position by means of the nuts i2, 42 (Figs. 1 and 2).

Removably mounted on the interior of the outer fixed shield or guard III is a spelter guard 41. Am suitable form of mounting which will permit the removal of the spelter guard to remove the excess spelter, or other coating material, thrown ofi of the coated articles and caught by the spelter guard 41, may be employed. I have shown the exterior of the spelter guard provided with three lugs 5|, 5|, Figs. 6 and 4, co-

operating with the pins 52, 52 immovably secured in the outer fixed shield or guard 54.

When it is necessary to clean out this spelter guard 41, to remove the excess spelter, or other coating material caught by it during the centrifugal action, it can be turned slightly to free thelugs 5|, 5| from the fixed pins 52, 82, Fig. 4, permitting it to drop into the oval water tank II, when it can be taken out and cleaned before replacing it on the lugs 5|, 5|. To assist in this operation, the fixed shield or guard ill is provided with a door 58, Figs. 2, 6 and '1. The door may be held closed by any suitable means, such as by the bolt 10, Fig. 7.

'Applicant is the patentee of U. S. Patent 1,662,537, granted March 13, 1928.

To fully understand the invention covered by this present application, it is necessary to comply with Sec. 4888 of the Revised Statutes, and to refer to the prior art, which is exemplified by this prior patent.

In the prior art, using a flaring basket, and relying on the centrifugal action to throw the coated articles out over the lip or edge of the basket, after the surplus coated' material had been removed, or partially removed, it is found impossibleto control the time that the articles are subjected to centrifugal action.

For example, it is found in practice that where a sumcient flare or incline is given to the sides of the basket to insure the coated articles, under the centrifugal action, rising from the bottom of the basket, they will be thrown over the lip or upper edge of the basket and into the cooling water before they have been sufiiciently stripped.

of their excess coating material. Moreover, a large portion of the free molten coating material will also be thrownlover the lip of the basket with the, coated articles.

If, on the the other. hand, the sides of the perforated basket are not inclined or flared sufficiently, the coated articles will remain in the basket and defeat the purpose of having the centrifugal action not only remove the excess coating material from the coated articles, and also automatically throw out of the basket such coated articles as have been properly processed to make room in the basket for new untreated coated articles.

Experience has shown that there is no middle ground where the coated articles will slowly move up the sides of the basket, to allow sufficient time for the necessary centrifugal treatment. The coated articles will either stay in the bottom of the basket when its sides have not a sufficient flare or incline, or will fly with great rapidity over the lip of the basket, where there is enough flare-or incline to move them upward at all.

It is also found that under the old method different sizes and shapes of articles require different inclines or flares to the sides of the basket, in order to cause them to rise under the centrifugal action. When once a suflicient incline is given to the sides of the basket for them to rise at all, they will immediately iiy out of the basket without having received the amount of centrifugal treatment to insure a smooth and ductile surface.

Furthermore, during the centrifugal operation where articles are discharged suddenly from the bottom over the top of the basket, a large portion of the molten excess coating will carry out over the top of the basket and move along with the coated articles and, at the same time, adhere to many of them, causing blisters, rough spots, and irregularities in the thickness of the coating.

Method of operation In my present invention the separate detached articles to be coated are first immersed in the.

molten metal bath of the coating material, which may be zinc, aluminum, tin, spelter, alloy, or any other suitable .coating material. For convenience in description I shall refer to the molten bath as being one of spelter;

While the articles coated may be any separate and detached articles I shall, for convenience, refer to them as wire nails, as illustrated in'F'igs. 8 to 10, though, of course, my invention is not to be confined to such articles.

The coated articles are fed on to the lip 29 of the fixed funnel 28 byany suitable means, in batches or continuously, and drop on to the conecollar 25, which distributes them'around the bottom of the perforated basket I8. As the basket is being rotated continuously, they are immediately subjected to centrifugal action, and move up the flaring or inclined sides of the basket I8.

This ductile coating is very important. Not only are articles made by my method or process superior to those made by the prior art, but they are safer, in that the coating metal on articles processed by my method has greater ductility and adherence to the metal of the article coated.

There have been instances where mechanics on several occasions have been blinded by flying spelter in driving nails or spikes where the zinc or spelter has flaked off and flown into the eye of the mechanic.

Tests on nails, spikes, bolts, screws, wire staples and numerous other articles coated by old methods indicate that a bend of 7 to 12 degrees is approximately the limit before the coating metal will crack and flake, Figs. 9 and 10. With my improved method, it is possible to coat small articles in a mass that will stand a bend of 180,

' Fig. 11, or more, without flaking the zinc coating.

clined surface, as shown, will work perfectly with.

articles of substantially the same size. It will work equally as well with larger or smaller Some of the excess coating material will be immediately thrown ofl and pass out through the perforations in the basket, and fall into the spelter catch or guard 41. Meanwhile, the articles continue to move up, the flaring or inclined sides of the basket l8 in their attempt to work their way immediately over the lip 60 of the basket, so that they could hit the inside surface of the fixed shield or guard 50, and then fall into the container 6|, mounted on wheels 62, 82, in the water trough 55. This container 6| can be wheeled out from under the centrifugal basket II, Fig. l, to remove the processed articles without stopping the machine.

However, in my invention, the coated articles do not move freely out of the centrifugal machine. Their free movement is retarded by one or more baiile plates 40, while still in the centrifugal basket l8, and while still at substantially their maximum temperature, and before the coating material can set.

By adjusting the edges of the baflle plates 40, 40 to or from the flaring or inclined surface of the centrifugal basket it, the Progress of the coated articles upward towards the lip 60 of the centrifugal basket is impeded and a certain percentage of the articles will be retarded and forced back into the bottom of the basket iii to raise again, thereby retaining the coated articles that much longer under the centrifugal action of the basket l8.

Some of the coated articles will pass through some of the openings 4|, 4| and 43, 43 in the different bafile plates 40, 40, by arranging, if necessary, these openings in each baffle plate staggered with relation to those in the next adjacent baifle plate; thereby the coated articles are further retained a sufficient length of time in the centrifugal basket l8 to insure that all the surplus coating material is rernoved from all the coated articles, and that the completely processed coated articles are smooth, without blemish, and have a ductile coating.

articles to be processed, by adjusting the baiiie or spider unit 36, on the cylindrical portion 3. of the flxed funnel, to or from the bottom of the basket l8, by loosening the nuts 42,. 42, and sliding the arms 38, 38 of the battle or spider unit 36. up or down, as permitted by the adjusting slots 39. 39.

I By using one basket it, having a given flare or inclined sides, and adjusting the bane or skeleton unit as described, different sized articles within a wide range may be processed with the same centrifugal basket l8. 7

One or more other centrifugal baskets. having difierent inclined or flared sides, may be used for articles of different sizes. So also diflerent sized bailie or spider units may be used with different centrifugal baskets i8.

It will be noted that in my invention the coated article while in the centrifugal baskets I 8, and whil the coating metal is substantially at its maximum temperature, and has had no opportunity to set or freeze, the coated articles are subjected to multiple percussion blows, by being thrown against the fixed baflles 40, 40.

These percussion blows are given the coated .of the spelter guard 41, so that no spelter, or

other coating metal or any coated article, can drop from the lip 80 into the spelter guard 41. I also preferably discontinue the perforations in the centrifugal basket l8 at an appreciable distance from the lip 60. the last perforations being on a line marked Hill, so that no excess spelter will be thrown out in the space IOI between the lip 60 and the spelter guard 41, to fall into the container 6|. 7

Having thus described my method, apparatus and new article of manufacture in connection with the illustrative embodiment thereof, of the details of which I do not desire to be limited, what I claim is new and what is desiredto be secured by Letters Patent is set forth in the appended claims.

What I claim is: l. The continuous method of treating a plurality of separate independent metal articles immediately after they have been coated by immersing them in a hot molten bath of the coating metal, consisting in feeding the coated articles continuously into the bottom of a-whirling basket of a centrifugal machine having upward flaring sides, and while the coating metal on the articles is substantially at the temperature of the said bath of molten coating metal, thereby subjecting the articles to centrifugal action while the coating metal is still liquid, impeding their normal movement to work up and out oi the basket until all thesruplus coating metal is removed, and continuously discharging the coated articles over the upper edge or, the basket,

2. The continuous method of treating a plurality of separate independent metal articles irnmedlately after they have been coated by immerslug there. in a hot molten both of the coating metal, consisting in feeding them into the bottomcf a whirling basket of a centrifugal incchine, said basket having upward flaring sides, and while the coated metal is substantially at the temperature of the said bath of molten coatingmetal, thereby subjectingthem to centrifugal action, and percussion blows against fixed bellies mounted within the basket, until all the surplus metal coating is removed.

3. The continuous method of treating a plura ity of separate independent metal articles immediately after they have. been coated by immersing them in a hot molten bath of the coatfixed non-rotatable spaced baffles mounted to project into the basket adjacent the inclined sides, and against which the articles treated are thrown to give them percussion blows while in, and subject to, the centrifugal action of the rotating basket to retard the movement of the treated articles out of the basket until all the surplus coating metal is removed from them.

6. In a centrifugal machine for removing surplus molten metal from coated articles, while the coating metal on the articles is still liquid, a centrlfugal basket mounted on a vertical axis and provided with anupward flaring or inclined sides tinuous movement to automatically work up and out of the basket until all the surplus coating is removed.

4. The continuous method of treating a pinrality of separate independent metal articles immediately after they have been coated by immersing them in a hot molten bath of the coating metal, consisting in feeding them into the bottom of a whirling basket of a centrifugal machine, said basket having upward flaring sides, and while the coated metal is substantially at the temperature of the said bath of molten coating metal, simultaneously subjecting them to centrifugal action and percussion blows against I a stationary baiiie while in the whirling basket so that the articles are subjected to centrifugal action and percussion blows at the same time, and causing them to follow a circuitous path through the basket in their normal movement to work up and out of the basket, until all the surplus metal coating is removed.

5. In a centrifugal machine for removing surplus molten metal from coated articles, while the coating metal on the articles is still liquid, a centrifugal basket mounted on a vertical axis and provided with an upward flaring or inclined sides to permit the coated articles treated to work their way automatically out over the rim of the basket, while the coating motel is still lluuid, and

to permit the coated articles treated to work their way automatically out over the rim of the basket, while the coating metal is still liquid, and fixed non-rotatable spaced bafiies mounted to project into the basket adjacent the inclined sides, and against which the articles treated aref thrown to give them percussion blows while in, and subject to, the centrifugal action of the re toting basket to retard the movement of the treated articles out of the basket until all the surplus coating metal is removed from them, and means to adjust the fixed non-rotatable bailie means to and from the daring or inclined sides of the basket to retard the automatic movement of the coated articles from the basket.

'7. In a. centrifugal machine'for removing surplus molten metal from coated article while the coating metal on the articles is. still liquid, 8. centrifugal basket mounted on a vertical axis, pro-- vided with upward, flaring 'orinclined sides to while the coating metal is still liquid, and fixedrnon-rotatable rigid percussion means, mounted toproject into the basket adjacent to the side walls of the basket and against which the coated articles are thrown while subject to centrifugal action of the basket thereby insuring that the percussion blows on the articles are given while the coated'articles are still subject to centrifugal action in their movement to automatically work out of the basket.

8. In a centrifugal machine for removing surplus molten metal frotn coated articles while the coating metal on the articles is still liquid, a centrifugal basket mounted on a vertical axis, provided with upward flaring or inclined sides, to permit the coated articles treated to work their way automatically out over the rim of the basket while {the coating metal is still liquid, and fixed non-rotatable .baflie means, including one or more bafiles mounted to project into the basket adjacent to the inclined sides of the basket, and

means to adjust said battles to or from the upward flaring sides of the basket.

9. In a centrifugal machine for removing surplus molten metal from coated articles, while the coating metal on the articles is still liquid, a centrifugal basket mounted on a vertical axis and provided with an upward flaring or inclined sides to permit the coated articles treated to work their way automatically out over the rim of the basket, while the coating metal is still liquid, and plural fixed non-rotatable baflles spaced from each other mounted to project into the basket adjacent to the inclined sides of the besket and spaced inwardly toward the axis, to retard the movement of the treated articles out of the basket until all the surplus coating metal is removed from them.

HENRY W. PLEIS'I'ER. 

